3 files changed, 525 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 8abbb2020af9..7951ad2fd995 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -468,6 +468,16 @@ config RTC_DRV_V3020
           This driver can also be built as a module. If so, the module
           will be called rtc-v3020.
 
+config RTC_DRV_WM8350
+        tristate "Wolfson Microelectronics WM8350 RTC"
+        depends on MFD_WM8350
+        help
+          If you say yes here you will get support for the RTC subsystem
+          of the Wolfson Microelectronics WM8350.
+
+          This driver can also be built as a module. If so, the module
+          will be called "rtc-wm8350".
+
 comment "on-CPU RTC drivers"
 
 config RTC_DRV_OMAP
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index e9e8474cc8fe..7a41201e7efd 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -66,4 +66,5 @@ obj-$(CONFIG_RTC_DRV_TEST)	+= rtc-test.o
 obj-$(CONFIG_RTC_DRV_TWL4030)   += rtc-twl4030.o
 obj-$(CONFIG_RTC_DRV_V3020)     += rtc-v3020.o
 obj-$(CONFIG_RTC_DRV_VR41XX)    += rtc-vr41xx.o
+obj-$(CONFIG_RTC_DRV_WM8350)    += rtc-wm8350.o
 obj-$(CONFIG_RTC_DRV_X1205)     += rtc-x1205.o
diff --git a/drivers/rtc/rtc-wm8350.c b/drivers/rtc/rtc-wm8350.c
new file mode 100644
index 000000000000..5c5e3aa91385
--- /dev/null
+++ b/drivers/rtc/rtc-wm8350.c
@@ -0,0 +1,514 @@
+/*
+ *      Real Time Clock driver for Wolfson Microelectronics WM8350
+ *
+ *      Copyright (C) 2007, 2008 Wolfson Microelectronics PLC.
+ *
+ *  Author: Liam Girdwood
+ *          linux@wolfsonmicro.com
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/interrupt.h>
+#include <linux/ioctl.h>
+#include <linux/completion.h>
+#include <linux/mfd/wm8350/rtc.h>
+#include <linux/mfd/wm8350/core.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+
+#define WM8350_SET_ALM_RETRIES  5
+#define WM8350_SET_TIME_RETRIES 5
+#define WM8350_GET_TIME_RETRIES 5
+
+#define to_wm8350_from_rtc_dev(d) container_of(d, struct wm8350, rtc.pdev.dev)
+
+/*
+ * Read current time and date in RTC
+ */
+static int wm8350_rtc_readtime(struct device *dev, struct rtc_time *tm)
+{
+        struct wm8350 *wm8350 = dev_get_drvdata(dev);
+        u16 time1[4], time2[4];
+        int retries = WM8350_GET_TIME_RETRIES, ret;
+
+        /*
+         * Read the time twice and compare.
+         * If time1 == time2, then time is valid else retry.
+         */
+        do {
+                ret = wm8350_block_read(wm8350, WM8350_RTC_SECONDS_MINUTES,
+                                        4, time1);
+                if (ret < 0)
+                        return ret;
+                ret = wm8350_block_read(wm8350, WM8350_RTC_SECONDS_MINUTES,
+                                        4, time2);
+                if (ret < 0)
+                        return ret;
+
+                if (memcmp(time1, time2, sizeof(time1)) == 0) {
+                        tm->tm_sec = time1[0] & WM8350_RTC_SECS_MASK;
+
+                        tm->tm_min = (time1[0] & WM8350_RTC_MINS_MASK)
+                            >> WM8350_RTC_MINS_SHIFT;
+
+                        tm->tm_hour = time1[1] & WM8350_RTC_HRS_MASK;
+
+                        tm->tm_wday = ((time1[1] >> WM8350_RTC_DAY_SHIFT)
+                                       & 0x7) - 1;
+
+                        tm->tm_mon = ((time1[2] & WM8350_RTC_MTH_MASK)
+                                      >> WM8350_RTC_MTH_SHIFT) - 1;
+
+                        tm->tm_mday = (time1[2] & WM8350_RTC_DATE_MASK);
+
+                        tm->tm_year = ((time1[3] & WM8350_RTC_YHUNDREDS_MASK)
+                                       >> WM8350_RTC_YHUNDREDS_SHIFT) * 100;
+                        tm->tm_year += time1[3] & WM8350_RTC_YUNITS_MASK;
+
+                        tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon,
+                                                    tm->tm_year);
+                        tm->tm_year -= 1900;
+
+                        dev_dbg(dev, "Read (%d left): %04x %04x %04x %04x\n",
+                                retries,
+                                time1[0], time1[1], time1[2], time1[3]);
+
+                        return 0;
+                }
+        } while (retries--);
+
+        dev_err(dev, "timed out reading RTC time\n");
+        return -EIO;
+}
+
+/*
+ * Set current time and date in RTC
+ */
+static int wm8350_rtc_settime(struct device *dev, struct rtc_time *tm)
+{
+        struct wm8350 *wm8350 = dev_get_drvdata(dev);
+        u16 time[4];
+        u16 rtc_ctrl;
+        int ret, retries = WM8350_SET_TIME_RETRIES;
+
+        time[0] = tm->tm_sec;
+        time[0] |= tm->tm_min << WM8350_RTC_MINS_SHIFT;
+        time[1] = tm->tm_hour;
+        time[1] |= (tm->tm_wday + 1) << WM8350_RTC_DAY_SHIFT;
+        time[2] = tm->tm_mday;
+        time[2] |= (tm->tm_mon + 1) << WM8350_RTC_MTH_SHIFT;
+        time[3] = ((tm->tm_year + 1900) / 100) << WM8350_RTC_YHUNDREDS_SHIFT;
+        time[3] |= (tm->tm_year + 1900) % 100;
+
+        dev_dbg(dev, "Setting: %04x %04x %04x %04x\n",
+                time[0], time[1], time[2], time[3]);
+
+        /* Set RTC_SET to stop the clock */
+        ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL, WM8350_RTC_SET);
+        if (ret < 0)
+                return ret;
+
+        /* Wait until confirmation of stopping */
+        do {
+                rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+                schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+        } while (retries-- && !(rtc_ctrl & WM8350_RTC_STS));
+
+        if (!retries) {
+                dev_err(dev, "timed out on set confirmation\n");
+                return -EIO;
+        }
+
+        /* Write time to RTC */
+        ret = wm8350_block_write(wm8350, WM8350_RTC_SECONDS_MINUTES, 4, time);
+        if (ret < 0)
+                return ret;
+
+        /* Clear RTC_SET to start the clock */
+        ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+                                WM8350_RTC_SET);
+        return ret;
+}
+
+/*
+ * Read alarm time and date in RTC
+ */
+static int wm8350_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+        struct wm8350 *wm8350 = dev_get_drvdata(dev);
+        struct rtc_time *tm = &alrm->time;
+        u16 time[4];
+        int ret;
+
+        ret = wm8350_block_read(wm8350, WM8350_ALARM_SECONDS_MINUTES, 4, time);
+        if (ret < 0)
+                return ret;
+
+        tm->tm_sec = time[0] & WM8350_RTC_ALMSECS_MASK;
+        if (tm->tm_sec == WM8350_RTC_ALMSECS_MASK)
+                tm->tm_sec = -1;
+
+        tm->tm_min = time[0] & WM8350_RTC_ALMMINS_MASK;
+        if (tm->tm_min == WM8350_RTC_ALMMINS_MASK)
+                tm->tm_min = -1;
+        else
+                tm->tm_min >>= WM8350_RTC_ALMMINS_SHIFT;
+
+        tm->tm_hour = time[1] & WM8350_RTC_ALMHRS_MASK;
+        if (tm->tm_hour == WM8350_RTC_ALMHRS_MASK)
+                tm->tm_hour = -1;
+
+        tm->tm_wday = ((time[1] >> WM8350_RTC_ALMDAY_SHIFT) & 0x7) - 1;
+        if (tm->tm_wday > 7)
+                tm->tm_wday = -1;
+
+        tm->tm_mon = time[2] & WM8350_RTC_ALMMTH_MASK;
+        if (tm->tm_mon == WM8350_RTC_ALMMTH_MASK)
+                tm->tm_mon = -1;
+        else
+                tm->tm_mon = (tm->tm_mon >> WM8350_RTC_ALMMTH_SHIFT) - 1;
+
+        tm->tm_mday = (time[2] & WM8350_RTC_ALMDATE_MASK);
+        if (tm->tm_mday == WM8350_RTC_ALMDATE_MASK)
+                tm->tm_mday = -1;
+
+        tm->tm_year = -1;
+
+        alrm->enabled = !(time[3] & WM8350_RTC_ALMSTS);
+
+        return 0;
+}
+
+static int wm8350_rtc_stop_alarm(struct wm8350 *wm8350)
+{
+        int retries = WM8350_SET_ALM_RETRIES;
+        u16 rtc_ctrl;
+        int ret;
+
+        /* Set RTC_SET to stop the clock */
+        ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+                              WM8350_RTC_ALMSET);
+        if (ret < 0)
+                return ret;
+
+        /* Wait until confirmation of stopping */
+        do {
+                rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+                schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+        } while (retries-- && !(rtc_ctrl & WM8350_RTC_ALMSTS));
+
+        if (!(rtc_ctrl & WM8350_RTC_ALMSTS))
+                return -ETIMEDOUT;
+
+        return 0;
+}
+
+static int wm8350_rtc_start_alarm(struct wm8350 *wm8350)
+{
+        int ret;
+        int retries = WM8350_SET_ALM_RETRIES;
+        u16 rtc_ctrl;
+
+        ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+                                WM8350_RTC_ALMSET);
+        if (ret < 0)
+                return ret;
+
+        /* Wait until confirmation */
+        do {
+                rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+                schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+        } while (retries-- && rtc_ctrl & WM8350_RTC_ALMSTS);
+
+        if (rtc_ctrl & WM8350_RTC_ALMSTS)
+                return -ETIMEDOUT;
+
+        return 0;
+}
+
+static int wm8350_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+        struct wm8350 *wm8350 = dev_get_drvdata(dev);
+        struct rtc_time *tm = &alrm->time;
+        u16 time[3];
+        int ret;
+
+        memset(time, 0, sizeof(time));
+
+        if (tm->tm_sec != -1)
+                time[0] |= tm->tm_sec;
+        else
+                time[0] |= WM8350_RTC_ALMSECS_MASK;
+
+        if (tm->tm_min != -1)
+                time[0] |= tm->tm_min << WM8350_RTC_ALMMINS_SHIFT;
+        else
+                time[0] |= WM8350_RTC_ALMMINS_MASK;
+
+        if (tm->tm_hour != -1)
+                time[1] |= tm->tm_hour;
+        else
+                time[1] |= WM8350_RTC_ALMHRS_MASK;
+
+        if (tm->tm_wday != -1)
+                time[1] |= (tm->tm_wday + 1) << WM8350_RTC_ALMDAY_SHIFT;
+        else
+                time[1] |= WM8350_RTC_ALMDAY_MASK;
+
+        if (tm->tm_mday != -1)
+                time[2] |= tm->tm_mday;
+        else
+                time[2] |= WM8350_RTC_ALMDATE_MASK;
+
+        if (tm->tm_mon != -1)
+                time[2] |= (tm->tm_mon + 1) << WM8350_RTC_ALMMTH_SHIFT;
+        else
+                time[2] |= WM8350_RTC_ALMMTH_MASK;
+
+        ret = wm8350_rtc_stop_alarm(wm8350);
+        if (ret < 0)
+                return ret;
+
+        /* Write time to RTC */
+        ret = wm8350_block_write(wm8350, WM8350_ALARM_SECONDS_MINUTES,
+                                 3, time);
+        if (ret < 0)
+                return ret;
+
+        if (alrm->enabled)
+                ret = wm8350_rtc_start_alarm(wm8350);
+
+        return ret;
+}
+
+/*
+ * Handle commands from user-space
+ */
+static int wm8350_rtc_ioctl(struct device *dev, unsigned int cmd,
+                            unsigned long arg)
+{
+        struct wm8350 *wm8350 = dev_get_drvdata(dev);
+
+        switch (cmd) {
+        case RTC_AIE_OFF:
+                return wm8350_rtc_stop_alarm(wm8350);
+        case RTC_AIE_ON:
+                return wm8350_rtc_start_alarm(wm8350);
+
+        case RTC_UIE_OFF:
+                wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+                break;
+        case RTC_UIE_ON:
+                wm8350_unmask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+                break;
+
+        default:
+                return -ENOIOCTLCMD;
+        }
+
+        return 0;
+}
+
+static void wm8350_rtc_alarm_handler(struct wm8350 *wm8350, int irq,
+                                     void *data)
+{
+        struct rtc_device *rtc = wm8350->rtc.rtc;
+        int ret;
+
+        rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
+
+        /* Make it one shot */
+        ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+                              WM8350_RTC_ALMSET);
+        if (ret != 0) {
+                dev_err(&(wm8350->rtc.pdev->dev),
+                        "Failed to disable alarm: %d\n", ret);
+        }
+}
+
+static void wm8350_rtc_update_handler(struct wm8350 *wm8350, int irq,
+                                      void *data)
+{
+        struct rtc_device *rtc = wm8350->rtc.rtc;
+
+        rtc_update_irq(rtc, 1, RTC_IRQF | RTC_UF);
+}
+
+static const struct rtc_class_ops wm8350_rtc_ops = {
+        .ioctl = wm8350_rtc_ioctl,
+        .read_time = wm8350_rtc_readtime,
+        .set_time = wm8350_rtc_settime,
+        .read_alarm = wm8350_rtc_readalarm,
+        .set_alarm = wm8350_rtc_setalarm,
+};
+
+#ifdef CONFIG_PM
+static int wm8350_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct wm8350 *wm8350 = dev_get_drvdata(&pdev->dev);
+        int ret = 0;
+        u16 reg;
+
+        reg = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+
+        if (device_may_wakeup(&wm8350->rtc.pdev->dev) &&
+            reg & WM8350_RTC_ALMSTS) {
+                ret = wm8350_rtc_stop_alarm(wm8350);
+                if (ret != 0)
+                        dev_err(&pdev->dev, "Failed to stop RTC alarm: %d\n",
+                                ret);
+        }
+
+        return ret;
+}
+
+static int wm8350_rtc_resume(struct platform_device *pdev)
+{
+        struct wm8350 *wm8350 = dev_get_drvdata(&pdev->dev);
+        int ret;
+
+        if (wm8350->rtc.alarm_enabled) {
+                ret = wm8350_rtc_start_alarm(wm8350);
+                if (ret != 0)
+                        dev_err(&pdev->dev,
+                                "Failed to restart RTC alarm: %d\n", ret);
+        }
+
+        return 0;
+}
+
+#else
+#define wm8350_rtc_suspend NULL
+#define wm8350_rtc_resume NULL
+#endif
+
+static int wm8350_rtc_probe(struct platform_device *pdev)
+{
+        struct wm8350 *wm8350 = platform_get_drvdata(pdev);
+        struct wm8350_rtc *wm_rtc = &wm8350->rtc;
+        int ret = 0;
+        u16 timectl, power5;
+
+        timectl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+        if (timectl & WM8350_RTC_BCD) {
+                dev_err(&pdev->dev, "RTC BCD mode not supported\n");
+                return -EINVAL;
+        }
+        if (timectl & WM8350_RTC_12HR) {
+                dev_err(&pdev->dev, "RTC 12 hour mode not supported\n");
+                return -EINVAL;
+        }
+
+        /* enable the RTC if it's not already enabled */
+        power5 = wm8350_reg_read(wm8350, WM8350_POWER_MGMT_5);
+        if (!(power5 &  WM8350_RTC_TICK_ENA)) {
+                dev_info(wm8350->dev, "Starting RTC\n");
+
+                wm8350_reg_unlock(wm8350);
+
+                ret = wm8350_set_bits(wm8350, WM8350_POWER_MGMT_5,
+                                      WM8350_RTC_TICK_ENA);
+                if (ret < 0) {
+                        dev_err(&pdev->dev, "failed to enable RTC: %d\n", ret);
+                        return ret;
+                }
+
+                wm8350_reg_lock(wm8350);
+        }
+
+        if (timectl & WM8350_RTC_STS) {
+                int retries;
+
+                ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+                                        WM8350_RTC_SET);
+                if (ret < 0) {
+                        dev_err(&pdev->dev, "failed to start: %d\n", ret);
+                        return ret;
+                }
+
+                retries = WM8350_SET_TIME_RETRIES;
+                do {
+                        timectl = wm8350_reg_read(wm8350,
+                                                  WM8350_RTC_TIME_CONTROL);
+                } while (timectl & WM8350_RTC_STS && retries--);
+
+                if (retries == 0) {
+                        dev_err(&pdev->dev, "failed to start: timeout\n");
+                        return -ENODEV;
+                }
+        }
+
+        device_init_wakeup(&pdev->dev, 1);
+
+        wm_rtc->rtc = rtc_device_register("wm8350", &pdev->dev,
+                                          &wm8350_rtc_ops, THIS_MODULE);
+        if (IS_ERR(wm_rtc->rtc)) {
+                ret = PTR_ERR(wm_rtc->rtc);
+                dev_err(&pdev->dev, "failed to register RTC: %d\n", ret);
+                return ret;
+        }
+
+        wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+        wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_PER);
+
+        wm8350_register_irq(wm8350, WM8350_IRQ_RTC_SEC,
+                            wm8350_rtc_update_handler, NULL);
+
+        wm8350_register_irq(wm8350, WM8350_IRQ_RTC_ALM,
+                            wm8350_rtc_alarm_handler, NULL);
+        wm8350_unmask_irq(wm8350, WM8350_IRQ_RTC_ALM);
+
+        return 0;
+}
+
+static int __devexit wm8350_rtc_remove(struct platform_device *pdev)
+{
+        struct wm8350 *wm8350 = platform_get_drvdata(pdev);
+        struct wm8350_rtc *wm_rtc = &wm8350->rtc;
+
+        wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+
+        wm8350_free_irq(wm8350, WM8350_IRQ_RTC_SEC);
+        wm8350_free_irq(wm8350, WM8350_IRQ_RTC_ALM);
+
+        rtc_device_unregister(wm_rtc->rtc);
+
+        return 0;
+}
+
+static struct platform_driver wm8350_rtc_driver = {
+        .probe = wm8350_rtc_probe,
+        .remove = __devexit_p(wm8350_rtc_remove),
+        .suspend = wm8350_rtc_suspend,
+        .resume = wm8350_rtc_resume,
+        .driver = {
+                .name = "wm8350-rtc",
+        },
+};
+
+static int __init wm8350_rtc_init(void)
+{
+        return platform_driver_register(&wm8350_rtc_driver);
+}
+module_init(wm8350_rtc_init);
+
+static void __exit wm8350_rtc_exit(void)
+{
+        platform_driver_unregister(&wm8350_rtc_driver);
+}
+module_exit(wm8350_rtc_exit);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("RTC driver for the WM8350");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm8350-rtc");